Projecting clocks provided with rotatable dials



May 13, 1958 E. STEFANI 2,834,250

PROJECTING CLOCKS PROVIDED WITH ROTATABLE DIALS Filed Dec. '7, 1955 2 Sheets-Sheet 1 INVENTOR E NEA STEFAN I BY 732M22 Ewe/ma ATTORNEY May 13, 1958 E. STEFAN! 2,834,250

PROJECTING CLOCKS PROVIDED WITH ROTATABLE DIALS Filed Dec. 7, 1955 2 Sheets-Sheet 2 INVENTOR ENEA STEFAN! BY 5- ELI/min] ATTORNEY PROJECTING CLOCKS PROVIDED -WITH ROTATABIJE"DIALS Enea Stefani, Bologna, Italy Application Deceniber-7 ,1955, Serial No. 551,640 Claims priority,- applie-ation Italy March 28,1955

4 Claims. (Cl.B8-.24)

:This invention relates to clocks.

'The main object of the inventiomisto provide aclock permitting of projecting against a screen the hours, so that the time may be readily read without difficulty even by sick or disabled people.

Another object of the invention is to provide a clock of the kind above referred to which may be mounted in fancy casings, or in particular pieces of furniture, in order to attain particular effects.

These and other objects, as will appear from the following specification are attained by fitting on the arbor or spindle or the hours wheel of a clock a transparent dial on which the-hours, and possibly other marking indicating hour fractions, are visible, being opaque or differently coloured, an opaque index being fitted on a fixed part or case of the clock in such a position as to indicate the time on the transparent rotatable dial, a simple lamp being provided on a part of the clock case opposite to said index and at a substantial distance therefrom for projecting said index and adjacent parts of the transparent dial a light cone of suitable small angle and projecting the numeral indicating the hour and possibly the markings indicating hour fractions together with the shadow of said index, on the ceiling or a wall of a room.

The rotatable dial is fitted on the arbor of the hours wheel and in which the minutes Wheel is omitted.

According to a second embodiment of the invention, the clock is provided with the usual non-transparent dial through which the arbors or spindles carrying the conventional hoursand minutes-hands project, while behind the first dial a second annular transparent dial is attached on a part of the hours wheel which co-acts with an opaque index of fixed hand fastened to a fixed part of the clock.

The invention will be better understood from the following specification of two preferred embodiments shown by way of example on the attached drawings in which:

Figures 1 and 2 show diagrammatically respectively in section and in front view an alarm clock in which the hours hand is replaced by a transparent rotatable dial and the minutes hand is omitted and,

Figures 3 and 4 show a conventional alarm clock in which, in addition to the usual parts, an annular dial is fitted on the hours wheel behind the conventional dial.

According to the embodiment as shown in Figures 1 and 2, in a case 3 a conventional clock mechanism is housed, which is provided with the hours wheel only whose arbor 101 instead of carrying a hand, carries a dial 2, which thus revolves together with the hours wheel. A screen cover 8 is provided on said dial. This cover is provided with an aperture 9 of such a width as to permit of seeing a suitable sector of the underlying dial 2.

Usually, the dial is made of an opaque material and the numerals indicating the hours and the marginal markings indicating fractions of hours are cut through the dial material or are otherwise made transparent. Of course, it is also possible to make the dial transparent Unitd es Patent 2,834,250 Patented -May 13, 1958 2 and themarkings opaque. Anyway,- radially through the sector-shapedaopenings '9- of thecove'r 8aepointer "-10 projects so as' to indicate the'hour orfrac'tion of hour at such a-distai tcefromsaid-"diatl, as t'o cau'se a smallangled cone of illumination to traverse said dial sector -in"-front of: saidwpening. 'The lamp 5 is connect'ed to a 'low voltage source as-through plug 6.

By this arrangement, when the lamp 5 is lighted, the numeral H indicating the hour and the'adjac'ent markings together with the {pointer "shadow 1 may be "projected against a suitable screen 14 lying at a distance of several metres (usually-bf the order of 2'n1'etres) ther'efromand for example a wall or, if the clock is placed with the dial up, as shown, against the ceiling, where it may be seen by all people in the same room. In order to permit of disposing the clock in this position, viz. with the dial up, a cylindrical wall 7 projects behind the clock case so as to house all projecting parts, including the windingand hour-setting keys.

According to the embodiment shown in Figures 3 an 4, the clock is provided with the usual fixed dial 22 and with the hoursand minutes-indicating hands 12, 112 but as a difference from the conventional (alarm) clocks, behind the fixed dial, in the front part 13 of the clock case 3 an annular dial 4 is fastened on a projecting part of the arbor 101 of the hours wheel. This dial is preferably made of transparent material and carries the nontransparent or otherwise differently coloured numerals indicating the hours. The clock case part 13 is provided with a transparent window 19 through which the hour or position between two hours, corresponding to the hours indicated by the usual hours hand, may be seen, possibly together with other markings indicating fractions of hours. Adjacent said window 19, a small transparent strip 29 is fitted, which carries a nontransparent or otherwise diiierently coloured pointer 10. Near the inside wall section of said annular dial 4, which is diametrically opposite to the wall section behind the said window 19, an electric lamp 5 is fitted, to which the current may be fed from the exterior through plug6. Thus a small-angled light beam of this lamp, by traversing the annular dial 4, projects on the ceiling of the room in which said clock is placed on an usual piece of furniture at a distance of the order of 2 metres the numeral H representing the hour and the shadow P of the pointer 10 suitably enlarged but sharply designed and well distinguishable from any person in the room.

In both cases, it has been found, as shown, that if the lamp 5 is arranged at a suitable distance, of the order of the diameter or thickness of an usual alarm clock (10 centimetres or more) from the part of the transparent rotatable dial which passes behind the window 9 (Figs. 1 and 2) or 19 (Fig. 3) as the case may be no expensive lenses system is needed and the cost of a clock, and especially of an alarm clock thus modified, is increased by i a negligible amount.

Of course, the clocks forming the object of the invention may undergo numerous changes without departing from the spirit of die invention or the scope of the appended claims.

What I claim is:

1. In a projecting clock combination having an arbor of the hours driven by a conventional clock mechanism mounted in a casing, a rotatable dial having transparent indicia fastened to said arbor for rotation therewith; a window in said clock casing in front of the transparent section of said dial; a non-transparent pointer projecting from said window through a transparent section of said window and pointing to the corresponding transparent indicia of the dial fastened to said hours wheel arbor, and an electric lamp arranged behind said dial fastened to a part of the said clock casingremote from said win- -dow whereby a shadow image of said transparent indicia and of said non-transparent pointer may be projected upon a viewing screen surface.

2. A clock according to claim 1, in which the rotatable dial fastened to the arbor of the hours is disk-shaped, said window and pointer are on the front side of the clock and said lamp being inside of the casing proximate to the rear wall thereof.

3. A clock according to claim 1, in which the rotatable dial fastened to the arbor of the hours is cylindrical with the window and pointer being provided on the upper part of the clock casing and the said lamp being arranged inside of said dial and mounted near the lower part of said casing. I

4. A clock according to claim 1, in which the rotatable dial fastened to the arbor of the hours is cylindrical, said window and pointer being on the upper part of the clock casing and the said lamp being arranged inside of said dial and mounted near the lower part of said casing; said dial being arranged behind the conventional fixed dial and being fastened to the said arbor of the hour behind and suitably spaced from the conventional hours hand.

References Cited in the file of this patent UNITED STATES PATENTS 1,619,096 Walsh Mar. 1, 1927 2,191,045 Slayton Feb. 20, 1940 2,351,238 Teuber June 13, 1944 2,471,800 Von Mulineau May 31, 1949 2,486,425 Loewe et al. Nov. 1, 1949 2,579,806 Dvorkin Dec. 25, 1951 2,641,159 Mihalakis June 9, 1953 2,641,160 Mihalakis June 9, 1953 2,694,338 1954 Moultry et al. Nov. 16, 

